SCN1A-Characterization of the Gene's Variants in the Polish Cohort of Patients with Dravet Syndrome: One Center Experience.

The aim of this study was to characterize the genotype and phenotype heterogeneity of patients with SCN1A gene mutations in the Polish population, fulfilling the criteria for the diagnosis of Dravet syndrome (DRVT). Particularly important was the analysis of the clinical course, the type of epileptic seizures and the co-occurrence of additional features such as intellectual disability, autism or neurological symptoms such as ataxia or gait disturbances. Based on their results and the available literature, the authors discuss potential predictors for DRVT. Identifying these early symptoms has important clinical significance, affecting the course and disease prognosis. 50 patients of the Pediatric Neurology Clinic of the Institute of Mother and Child in Warsaw clinically diagnosed with DRVT and carriers of SCN1A pathogenic variants were included. Clinical data were retrospectively collected from caregivers and available medical records. Patients in the study group did not differ significantly in parameters such as type of first seizure and typical epileptic seizures from those described in other studies. The age of onset of the first epileptic seizure was 2-9 months. The co-occurrence of intellectual disability was confirmed in 71% of patients and autism in 18%. The study did not show a correlation between genotype and phenotype, considering the severity of the disease course, clinical symptoms, response to treatment, the presence of intellectual disability, autism symptoms or ataxia. From the clinical course, a significant problem was the differentiation between complex febrile convulsions and symptoms of DRVT. The authors suggest that parameters such as the age of the first seizure, less than one year of age, the onset of a seizure up to 72 h after vaccination and the presence of more than two features of complex febrile seizures are more typical of DRVT, which should translate into adequate diagnostic and clinical management. The substantial decrease in the age of genetic verification of the diagnosis, as well as the decline in the use of sodium channel inhibitors, underscores the growing attention of pediatric neurologists in Poland to the diagnosis of DRVT.

ADCY5-related dyskinesia - case series with literature review.

INTRODUCTION: ADCY5-related dyskinesia is a rare neurological disease caused by mutations in the gene encoding the adenylyl cyclase 5 (ADCY5) isoform, a protein that plays an important role in intracellular transmission. Variants in ADCY5 are associated with a spectrum of neurological disease encompassing dyskinesia, chorea, and dystonia. State of the-art. ADCY5 mutations result in clinically heterogeneous manifestations which comprise a range of core and less to highly variable symptoms. Due to the heterogeneous nature and difficulty in diagnosis of the disorder, available treatments are highly limited. CLINICAL IMPLICATIONS: ADCY5-related dyskinesia was reported in 52 individuals in the literature over a five-year period (January 2017 to January 2022). We have listed all the symptoms and their frequency. The most common symptom reported in these patients was dystonia. Over 50% of patients developed dyskinesia and chorea. We report two cases of familial occurrence of symptomatic ADCY5-related dyskinesia. A 45-year-old patient presented with involuntary movements which had been occurring since childhood. The proband's neurological examination revealed dysarthria, involuntary myoclonic twitches, and choreic movements. The patient's 9-year-old son had developed involuntary movements, mainly chorea and dystonia. FUTURE DIRECTIONS: This paper aims to summarise the recent literature on ADCY5-related neurological disorders and to present a new case of a Polish family with ADCY5 mutation. Genetic diagnostics are important in the context of possible future targeted treatments.

Genetic Risk Factors for Neurological Disorders in Children with Adverse Events Following Immunization: A Descriptive Study of a Polish Case Series.

Studies conducted on large populations show a lack of connection between vaccination and serious neurological symptoms. However, there are isolated cases that indicate such a relationship. These reports on adverse effects following immunization (AEFI) reduce social confidence in vaccination; however, their background may be rare genetic defects. The aim of the presented study was to examine if neurological AEFI in children may be associated with variants in genes related to neurodevelopment. To identify such possible associations, a descriptive study of the Polish case series was conducted. We performed next-generation sequencing in patients who, up to 4 weeks of injection of any vaccine, manifested neurological AEFI. We included 23 previously normally developing children with first seizures that occurred after vaccination. We identified pathogenic/likely pathogenic variants in genes engaged in neurodevelopment in nine patients and variants of uncertain significance in another nine patients. The mutated genes belonged to the group of genes related to epilepsy syndromes/epileptic encephalopathy. We showed that AEFI might have a genetic background. We hypothesized that in some AEFI patients, the vaccine might only trigger neurological symptoms that would have been manifested anyway as a result of a pathogenic variant in a gene engaged in neurodevelopment.

The Generation of Human iPSC Lines from Three Individuals with Dravet Syndrome and Characterization of Neural Differentiation Markers in iPSC-Derived Ventral Forebrain Organoid Model.

Dravet syndrome (DRVT) is a rare form of neurodevelopmental disorder with a high risk of sudden unexpected death in epilepsy (SUDEP), caused mainly (>80% cases) by mutations in the SCN1A gene, coding the Nav1.1 protein (alfa-subunit of voltage-sensitive sodium channel). Mutations in SCN1A are linked to heterogenous epileptic phenotypes of various types, severity, and patient prognosis. Here we generated iPSC lines from fibroblasts obtained from three individuals affected with DRVT carrying distinct mutations in the SCN1A gene (nonsense mutation p.Ser1516*, missense mutation p.Arg1596His, and splicing mutation c.2589+2dupT). The iPSC lines, generated with the non-integrative approach, retained the distinct SCN1A gene mutation of the donor fibroblasts and were characterized by confirming the expression of the pluripotency markers, the three-germ layer differentiation potential, the absence of exogenous vector expression, and a normal karyotype. The generated iPSC lines were used to establish ventral forebrain organoids, the most affected type of neurons in the pathology of DRVT. The DRVT organoid model will provide an additional resource for deciphering the pathology behind Nav1.1 haploinsufficiency and drug screening to remediate the functional deficits associated with the disease.

Dravet Syndrome-The Polish Family's Perspective Study.

AIM: The aim of the paper is to study the prevalence of Dravet Syndrome (DS) in the Polish population and indicate different factors other than seizures reducing the quality of life in such patients. METHOD: A survey was conducted among caregivers of patients with DS by the members of the Polish support group of the Association for People with Severe Refractory Epilepsy DRAVET.PL. It included their experience of the diagnosis, seizures, and treatment-related adverse effects. The caregivers also completed the PedsQL survey, which showed the most important problems. The survey received 55 responses from caregivers of patients with DS (aged 2-25 years). RESULTS: Prior to the diagnosis of DS, 85% of patients presented with status epilepticus lasting more than 30 min, and the frequency of seizures (mostly tonic-clonic or hemiconvulsions) ranged from 2 per week to hundreds per day. After the diagnosis of DS, patients remained on polytherapy (drugs recommended in DS). Before diagnosis, some of them had been on sodium channel blockers. Most patients experienced many adverse effects, including aggression and loss of appetite. The frequency of adverse effects was related to the number of drugs used in this therapy, which had an impact on the results of the PedsQL form, particularly in terms of the physical and social spheres. Intensive care unit stays due to severe status epilepticus also had an influence on the results of the PedsQL form. CONCLUSIONS: Families must be counseled on non-pharmacologic strategies to reduce seizure risk, including avoidance of triggers that commonly induce seizures (including hyperthermia, flashing lights and patterns, sleep abnormalities). In addition to addressing seizures, holistic care for a patient with Dravet syndrome must involve a multidisciplinary team that includes specialists in physical, occupational and speech therapy, neuropsychology, social work.

The spectrum of intermediate SCN8A-related epilepsy.

OBJECTIVE: Pathogenic variants in SCN8A have been associated with a wide spectrum of epilepsy phenotypes, ranging from benign familial infantile seizures (BFIS) to epileptic encephalopathies with variable severity. Furthermore, a few patients with intellectual disability (ID) or movement disorders without epilepsy have been reported. The vast majority of the published SCN8A patients suffer from severe developmental and epileptic encephalopathy (DEE). In this study, we aimed to provide further insight on the spectrum of milder SCN8A-related epilepsies. METHODS: A cohort of 1095 patients were screened using a next generation sequencing panel. Further patients were ascertained from a network of epilepsy genetics clinics. Patients with severe DEE and BFIS were excluded from the study. RESULTS: We found 36 probands who presented with an SCN8A-related epilepsy and normal intellect (33%) or mild (61%) to moderate ID (6%). All patients presented with epilepsy between age 1.5 months and 7 years (mean = 13.6 months), and 58% of these became seizure-free, two-thirds on monotherapy. Neurological disturbances included ataxia (28%) and hypotonia (19%) as the most prominent features. Interictal electroencephalogram was normal in 41%. Several recurrent variants were observed, including Ile763Val, Val891Met, Gly1475Arg, Gly1483Lys, Phe1588Leu, Arg1617Gln, Ala1650Val/Thr, Arg1872Gln, and Asn1877Ser. SIGNIFICANCE: With this study, we explore the electroclinical features of an intermediate SCN8A-related epilepsy with mild cognitive impairment, which is for the majority a treatable epilepsy.

Friedreich ataxia is not only a GAA repeats expansion disorder: implications for molecular testing and counselling.

Friedreich ataxia (FRDA) is the most common hereditary ataxia. It is an autosomal recessive disorder caused by mutations of the FXN gene, mainly the biallelic expansion of the (GAA)n repeats in its first intron. Heterozygous expansion/point mutations or deletions are rare; no patients with two point mutations or a point mutation/deletion have been described, suggesting that loss of the FXN gene product, frataxin, is lethal. This is why routine FRDA molecular diagnostics is focused on (GAA)n expansion analysis. Additional tests are considered only in cases of heterozygous expansion carriers and an atypical clinical picture. Analyses of the parent's carrier status, together with diagnostic tests, are performed in rare cases, and, because of that, we may underestimate the frequency of deletions. Even though FXN deletions are characterised as 'exquisitely rare,' we were able to identify one case (2.4 %) of a (GAA)n expansion/exonic deletion in a group of 41 probands. This was a patient with very early onset of disease with rapid progression of gait instability and hypertrophic cardiomyopathy. We compared the patient's clinical data to expansion/deletion carriers available in the literature and suggest that, in clinical practice, the FXN deletion test should be taken into account in patients with early-onset, rapid progressive ataxia and severe scoliosis.

The spectrum of PLP1 gene mutations in patients with the classical form of the Pelizaeus-Merzbacher disease.

UNLABELLED: The Pelizaeus-Merzbacher disease (PMD) is a rare X-linked recessive hypomyelination disorder caused by mutations of the proteolipid protein1 gene (PLP1). There is a spectrum of PLP1-related disorders from very severe connatal PMD, through classical PMD to mild spastic paraplegia type 2 (SPG2), with some correlation between the type of mutation and the phenotype. In general, missense mutations give rise to more severe forms of the disease, deletions and null mutations to mild PMD and SPG2. The most common variations, duplications, result in the classical-intermediate form of PMD. THE AIM: To report the analysis of mutations in the PLP1 gene and phenotype di!erences in ten male patients diagnosed with PMD. Although they had different types of PLP1 mutations (duplications, missense and nonsense mutations), all of them were clinically classi"ed with the classical form of PMD (clPMD). MATERIAL AND METHODS: The subjects of analysis were ten male patients aged 1.5 to 21 years who were diagnosed with PMD. All patients developed the "rst clinical symptoms between 1 an 8 months of age and showed developmental delay, mainly in motor skills. All were classified with the classical form of the disease, according to international clinical criteria and the electrophysiological and brain MRI criteria of hypomyelination. The molecular analysis of the PLP1 gene involved dosage analysis and direct sequencing of all exons and promotor region of the gene. RESULTS: The clinical diagnosis of PMD was con"rmed for all subjects by molecular analysis of the PLP1gene. Although all had the classical form of PMD, it was caused by mutations of di!erent types: duplications of the entire gene, missense and nonsense mutations. CONCLUSIONS: Our clinical and molecular "ndings showed that the phenotypic spectrum resulting from PLP1 mutations seems to be broader in patients with the PLP1 gene duplication compared to patients with both nonsense and missense mutation. Nevertheless, apart from the type of mutation, all our patients' clinical manifestation falls into the category of the classical form of PMD according to international criteria. Obviously the type of mutations, but also other unidentified factors may a!ect the clinical course of PMD.The Pelizaeus-Merzbacher disease (PMD) is a rare X-linked recessive hypomyelination disorder caused by mutations of the proteolipid protein 1 gene (PLP1). There is a spectrum of PLP1-related disorders from very severe connatal PMD, through classical PMD to mild spastic paraplegia type 2 (SPG2), with some correlation between the type of mutation and the phenotype. In general, missense mutations give rise to more severe forms of the disease, deletions and null mutations to mild PMD and SPG2. The most common variations, duplications, result in the classical-intermediate form of PMD. THE AIM: To report the analysis of mutations in the PLP1 gene and phenotype differences in ten male patients diagnosed with PMD. Although they had di!erent types of PLP1 mutations (duplications, missense and nonsense mutations), all of them were clinically classi"ed with the classical form of PMD (clPMD). MATERIAL AND METHODS: The subjects of analysis were ten male patients aged 1.5 to 21 years who were diagnosed with PMD. All patients developed the "rst clinical symptoms between 1 an 8 months of age and showed developmental delay, mainly in motor skills. All were classified with the classical form of the disease, according to international clinical criteria and the electrophysiological and brain MRI criteria of hypomyelination. The molecular analysis of the PLP1 gene involved dosage analysis and direct sequencing of all exons and promotor region of the gene. RESULTS: The clinical diagnosis of PMD was con"rmed for all subjects by molecular analysis of the PLP1 gene. Although all had the classical form of PMD, it was caused by mutations of di!erent types: duplications of the entire gene, missense and nonsense mutations. CONCLUSIONS: Our clinical and molecular findings showed that the phenotypic spectrum resulting from PLP1 mutations seems to be broader in patients with the PLP1 gene duplication compared to patients with both nonsense and missense mutation. Nevertheless, apart from the type of mutation, all our patients' clinical manifestation falls into the category of the classical form of PMD according to international criteria. Obviously the type of mutations, but also other unidentified factors may a!ect the clinical course of PMD.

Application of array comparative genomic hybridization in 102 patients with epilepsy and additional neurodevelopmental disorders.

Copy-number variants (CNVs) collectively represent an important cause of neurodevelopmental disorders such as developmental delay (DD)/intellectual disability (ID), autism, and epilepsy. In contrast to DD/ID, for which the application of microarray techniques enables detection of pathogenic CNVs in -10-20% of patients, there are only few studies of the role of CNVs in epilepsy and genetic etiology in the vast majority of cases remains unknown. We have applied whole-genome exon-targeted oligonucleotide array comparative genomic hybridization (array CGH) to a cohort of 102 patients with various types of epilepsy with or without additional neurodevelopmental abnormalities. Chromosomal microarray analysis revealed 24 non-polymorphic CNVs in 23 patients, among which 10 CNVs are known to be clinically relevant. Two rare deletions in 2q24.1q24.3, including KCNJ3 and 9q21.13 are novel pathogenic genetic loci and 12 CNVs are of unknown clinical significance. Our results further support the notion that rare CNVs can cause different types of epilepsy, emphasize the efficiency of detecting novel candidate genes by whole-genome array CGH, and suggest that the clinical application of array CGH should be extended to patients with unexplained epilepsies.

Recurrent distal 7q11.23 deletion including HIP1 and YWHAG identified in patients with intellectual disabilities, epilepsy, and neurobehavioral problems.

We report 26 individuals from ten unrelated families who exhibit variable expression and/or incomplete penetrance of epilepsy, learning difficulties, intellectual disabilities, and/or neurobehavioral abnormalities as a result of a heterozygous microdeletion distally adjacent to the Williams-Beuren syndrome region on chromosome 7q11.23. In six families with a common recurrent ∼1.2 Mb deletion that includes the Huntingtin-interacting protein 1 (HIP1) and tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein gamma (YWHAG) genes and that is flanked by large complex low-copy repeats, we identified sites for nonallelic homologous recombination in two patients. There were no cases of this ∼1.2 Mb distal 7q11.23 deletion copy number variant identified in over 20,000 control samples surveyed. Three individuals with smaller, nonrecurrent deletions (∼180-500 kb) that include HIP1 but not YWHAG suggest that deletion of HIP1 is sufficient to cause neurological disease. Mice with targeted mutation in the Hip1 gene (Hip1⁻(/)⁻) develop a neurological phenotype characterized by failure to thrive, tremor, and gait ataxia. Overall, our data characterize a neurodevelopmental and epilepsy syndrome that is likely caused by recurrent and nonrecurrent deletions, including HIP1. These data do not exclude the possibility that YWHAG loss of function is also sufficient to cause neurological phenotypes. Based on the current knowledge of Hip1 protein function and its proposed role in AMPA and NMDA ionotropic glutamate receptor trafficking, we believe that HIP1 haploinsufficiency in humans will be amenable to rational drug design for improved seizure control and cognitive and behavioral function.

[Variable clinical expression of familial Incontinentia Pigmenti syndrome - presentation of three cases]. / Zróznicowanie ekspresji fenotypowej rodzinne wystepujacego zespolu Incontinentia Pigmenti - prezentacja trzech przypadków.

Incontinentia Pigmenti (IP, Bloch-Sulzberger syndrome, OMIM 308300) is a rare X-linked dominant genodermatosis, usually lethal in males in the prenatal period. Wide spectrum of clinical expression consists of skin hyperpigmented lines and swirling patterns, dysplastic teeth and nails, and in 30% central nervous system abnormalities including seizures, microcephaly and intellectual disability (10% of cases). In 80% of IP cases, the disease is caused by a large-scale deletion of exons 4 to 10 of the NEMO gene. Three cases of variable expression of Incontinentia Pigmenti are presented. In a one-year-old girl, her mother and grandmother molecular analysis revealed the same typical deletion of the NEMO gene. In the proband, characteristic skin lesions were detected located over the trunk and lower limbs. Characteristic evolution of the changes was observed. In the mother, expression of the disease was much milder, whereas in the grandmother lesions were restricted to the fingernails. Clinical characteristics and pedigree data are described.

[Erythema nodosum in a child with salmonellosis]. / Rumien guzowaty u dziecka z salmonelloza.

We report a case of 4-years-old girl who suffered one episode of clinically typical erythema nodosum and arthralgia of short duration. Stool culture showed growth of Salmonella enteritidis. Levels of serum anti-Salmonella antibodies and immunocomplexes lowered during resolution of skin nodules. Erythema nodosum probably results from the formation of immunocomplexes and their deposition in and around blood vessels of the skin. Salmonellosis should be considered in patients presenting with erythema nodosum. Routine stool culture might provide an important diagnostic clue.